Use experimental config types in pfunit tests

Demonstrates use of the config types in pfunit tests. Merges all the asym_geo_* tests into one file (still separate tests), removing the need for separate input files. Module-level fixture removes some repeated code, including parameters that were in the input files.

It would be nice to remove the need to call config_type%setup(...)

• WIP: convert pfunit test to use config

• Convert all asym_geo* tests to use configs, move into single test

• Use setup/teardown to avoid repeated code in asym geo tests

  Note that this annoyingly introduces a warning for the unused dummy variable this

• Use config_type implicit constructor to avoid repeated code

  Avoids naming the variable on multiple lines